Sally Hunt, the general secretary of the University and College Union, is due to tell the Trades Union Congress in Manchester that the new administration appears “ready and willing” to renege on an age-old pledge to “expand learning and increase opportunity”.

“In cutting spending on education and learning the Tories and the Lib Dems close their eyes to the lessons of history,” she will say. “They close their eyes to the fact that it was government investment that made British universities the envy of the world. That learning is important for its own sake, not solely as a driver for growth and prosperity.”

Her speech follows warnings from other union leaders at the congress that there will be coordinated action against public spending cuts to be announced in the Comprehensive Spending Review on 20 October.

Times Higher Education disclosed last month that Sir Gus O’Donnell, the Cabinet secretary, had warned vice-chancellors to plan for cuts of up to 35 per cent to public funding.

Ms Hunt will tell delegates that more than £2.5 million was spent on the private school education of just 12 members of the current Cabinet, all of whom then went to enjoy a free university education.

She will add that they are now “happy to deny hundreds of thousands of young people the opportunities that they themselves were given, by cutting £1.4 billion from further and higher education budgets”.

The union leader will also attack the coalition government’s decision to reduce corporation tax, saying that restoring it to the G7 average would raise sufficient money to abolish tuition fees.